"The career of a young theoretical physicist consists of treating the
harmonic oscillator in ever-increasing levels of abstraction."

-- Sidney Coleman.

David Tong: Lectures on Quantum Field Theory

These lecture notes are based on an introductory course on quantum
field theory, aimed at Part III (i.e. masters level) students.
The full set of lecture notes can be downloaded here, together with videos
of the course when it was repeated at the Perimeter Institute. Individual sections
can be downloaded below. Last updated April 2015.

Quantum Field Theory on the Web

Philip Tanedo, who took this course long ago, has put together a
useful
literature review of quantum field theory textbooks.

Some Classic Quantum Field Theory Courses

The late Sidney Coleman taught the quantum field theory course at Harvard
for many years, influencing a generation of physicists in the way
they view and teach QFT. Below you can find the pdf files of handwritten
lecture notes for Coleman's course (transcribed by Brian Hill). The notes come in two large
files, each around 6.5 Mb.